Gate Engineered Ferroelectric Junctionless BioFET for Label-Free Detection of Biomolecules

Abstract

A Gate Engineered Ferroelectric Junctionless BioFET is proposed and investigated for label-free detection of various biomolecules. A nanocavity is created by etching a part of the gate oxide material on the top and bottom of the device, which allows biomolecules to get immobilized. The immobilization of biomolecules in the cavity causes changes in electrostatic characteristics such as surface potential, input and output characteristics, transconductance, output conductance, gate capacitance, and cut-off frequency used as sensing metrics. The biosensor is also examined at different biomolecule concentrations, such as -1e12, 0, and 1e12. The transistor's sensitivity is then understood by looking at the fluctuation in threshold voltage, subthreshold swing, and switching ratio. Ferroelectric Junctionless BioFET and Gate Engineered Ferroelectric Junctionless BioFET performances have been compared. It has been found that the Gate Engineered Ferroelectric Junctionless BioFET shows the maximum improvement for protein (1202.4%, 111%, and 565%) and DNA (787.5%, 117.3%, and 600%). For ultrasensitive bio-sensing applications, the Gate Engineered Ferroelectric Junctionless BioFET is shown to be suitable.